Using a signal mapper

On the #pyqt channel on Freenode, lauri asked about connecting identically-named signals with different parameters from QSignalMapper to slots.

The following example uses old-style signals and slots connections to explicitly specify the signals to be connected to slots in a Python subclass of QWidget.

 1 import sys
 2 from PyQt4.QtCore import *
 3 from PyQt4.QtGui import *
 4 
 5 class Window(QWidget):
 6 
 7  def __init__(self, parent = None):
 8  
 9  QWidget.__init__(self, parent)
 10  
 11  layout = QVBoxLayout(self)
 12  mapper = QSignalMapper(self)
 13  
 14  for i in range(5):
 15  
 16  button = QPushButton()
 17  button.setText("Button " + str(i))
 18  self.connect(button, SIGNAL("clicked()"), mapper, SLOT("map()"))
 19  if i % 2 == 0:
 20  mapper.setMapping(button, str(i))
 21  else:
 22  mapper.setMapping(button, i)
 23  layout.addWidget(button)
 24  
 25  self.connect(mapper, SIGNAL("mapped(const QString &)"), self.stringMapped)
 26  self.connect(mapper, SIGNAL("mapped(int)"), self.intMapped)
 27  
 28  def stringMapped(self, value):
 29  
 30  print "stringMapped", value
 31  
 32  def intMapped(self, value):
 33  
 34  print "intMapped", value
 35  
 36 
 37 if __name__ == "__main__":
 38 
 39  app = QApplication(sys.argv)
 40  window = Window()
 41  window.show()
 42  sys.exit(app.exec_())